Contact switches formed in MEMS (Micro-Electro-Mechanical Systems) technology are well-suited for switching broadband signals. For example, MEMS switches can provide switching of signals covering frequencies from DC to over 20 GHz. MEMS switches have smaller physical size and higher switching speed than conventional electromechanical switches. MEMS switches also have lower insertion loss in the ON state, higher isolation in the OFF state, and lower distortion in both the ON and OFF states than conventional high frequency semiconductor switches. MEMS switches have high reliability when “cold switched”, i.e. switched between ON and OFF states, or OFF and ON states, with no signal power applied. When cold switched, MEMS switches can operate reliably for as many as 109 switching cycles.
A significant drawback of MEMS switches is the decreased reliability that results when the MEMS switches are “hot switched”, i.e. switched between ON and OFF states, or OFF and ON states, when signal power is applied to the MEMS switches. While reliability of the MEMS switches typically has an inverse relationship to the level of the signal power that is applied during switching, the reliability of the MEMS switches can rapidly decrease when the signal power applied during switching is greater than a threshold power level that depends on the type of MEMS switch. At applied signal power levels that are greater than the threshold power level, the number of switching cycles of reliable operation can decrease substantially.